Learning Objectives

Week 1:

Define and identify how frequency and intensity appear in a sine wave

• Frequency in a Sine Wave:

  • The number of cycles (complete waves) per second

  • Measured in Hertz (Hz)

  • Determines the pitch of the sound (higher frequency = higher pitch)

  • One cycle corresponds to one compression and one rarefaction in the wave

  • Identify: how many waves per second

• Intensity in a Sine Wave:

  • Related to how tall or large the wave is (amplitude)

  • The taller the wave, the greater the intensity or loudness

  • Intensity influences how loud the sound is perceived

  • Identify: how tall the waves are

Frequency refers to the number of complete cycles (one compression and one rarefaction) a sine wave completes per second and is measured in Hertz (Hz). It determines the pitch of the sound, with higher frequencies producing higher pitches. Intensity is related to the amplitude or height of the sine wave; the taller the wave, the greater the intensity, which corresponds to how loud the sound is perceived.

Week 1:

Describe phase and interference in a sine wave

• Phase in a Sine Wave:

  • Refers to the position or stage of a point within one cycle of a sine wave

  • Relationship b/w the shape of waves

  • What stage in the wave

  • Measured in degrees (0°, 90°, 270°, 360°)

  • Determines how two waves align when they meet

• Interference in a Sine Wave:

  • Happens when two sine waves overlap in the same medium

  • Constructive interference: waves are in phase, their amplitudes add up, producing a larger wave

  • Destructive interference: waves are out of phase (e.g., 180° difference), their amplitudes cancel out, producing a smaller or zero wave

  • Partial interference occurs when phase difference is between 0° and 180°, waves partially add or subtract

Phase is the specific point in the cycle of a sine wave, measured in degrees or radians, indicating where the wave is in its repetition. Interference occurs when two sine waves meet: if they are in phase, constructive interference causes the amplitudes to add, making the sound louder; if they are out of phase, destructive interference causes the amplitudes to cancel, reducing or eliminating the sound. Partial interference results when the phase difference is between these extremes.

Week 1:

Explain the difference between a pure tone and a complex sound

• Pure Tone:

  • Consists of one frequency only

  • Its waveform is a sine wave (one cycle of compression and rarefaction)

  • Represents a simple periodic sound

• Complex Sound:

  • Made up of multiple frequencies combined

  • Not a simple sine wave waveform

  • Many natural sounds (such as speech sounds) are complex sounds

  • Consists of a fundamental frequency plus other frequencies (harmonics) combined

  • More common in everyday sounds than pure tones

A pure tone consists of only one frequency, and its waveform is a simple sine wave with one cycle of compression and rarefaction. It is a basic, periodic sound. In contrast, a complex sound is made up of many frequencies combined, so its waveform is not a pure sine wave but a pattern that repeats over time. Complex sounds include a fundamental frequency plus additional frequencies called harmonics. Most sounds we hear in everyday life, like speech and musical instruments, are complex sounds rather than pure tones.

Week 1:

List 5 characteristics of a decibel

1. Involves ratios

2. Utilizes a logarithm

3. Is, therefore, nonlinear

4. Is expressed in terms of reference levels

5. Is a relative unit of measure

Week 1:

Demonstrate how sound pressure level and intensity level influence amplitude